Such a trim element, for example designed to be placed in a vehicle, has at least one localized foam layer, the location of which is chosen by choosing the position of the peripheral wall on the outer face of the support element. A trim element is thus obtained having the desired appearance and which can adapt to its environment by for example having “foamed” areas designed to be visible and other, so-called “technical” areas, which are not foamed and are designed to receive functional elements of the vehicle or to perform a particular function in a vehicle.
Such a trim element is produced by performing “partial” foaming on the outer face of the support element using a suitable production tool, the foaming being done only in the central area(s) where a layer of foam must be located. To that end, the tool for producing the trim element must be adapted to allow that partial foaming by providing one or more foaming cavities only opposite the central area(s) of the support element. A problem arises of positioning the support element in the production tool so as to precisely match the central area(s) of the support element with the foaming cavity or cavities provided in the production tool. To that end, the peripheral wall at least partially surrounding the central area designed to be foamed may be used, since the shape of the foaming cavity is suitable for receiving the peripheral wall in a bearing manner. However, the peripheral wall is not sufficient to ensure correct positioning of the central area in the foaming cavity, which can cause appearance defects in the finished trim element if the foaming has not been done accurately in the central area(s) designed to receive a layer of foam.
To improve the positioning of the support element, and in particular of the central area(s), in the production tool, it is known to provide additional positioning elements in the production tool. FIG. 2 shows such positioning elements produced in the form of lugs A, optionally retractable, extending protruding into the foaming cavity B and designed to be inserted in the corresponding openings C of the support element D and positioned in the central area(s) of the support element. When the lugs A are inserted in the corresponding openings C, this means that the support element is correctly positioned in the production tool and that the foaming can be done without risk of foaming an area of the support element that should not be foamed or without risk of the foam overflowing the central area. In order to prevent foam leakage through the openings C of the support element during foaming, covering elements E are positioned on the outer face of the support element so as to cover the openings C. These covering elements are for example pieces of adhesive sheets or elastic membranes. There are for example four openings C per central area of the support element and an equal number of positioning lugs A.
Such a method for positioning the support element in the production tool is not satisfactory, as it causes an increase in the production cost of the trim element due to the presence of the covering elements and a decreased production rhythm due to the time necessary to position those covering elements on the openings of the support element.
Another method provides for using a particular shape of the support element, and in particular the face thereof pressed against the production tool. However, such a method involves making the shape of the central area dependent on the need to position the support element in the production tool.